Funding for this research was provided by:
The Norwegian ExtraFoundation for Health and Rehabilitation (2015/FO5150)
Text and Data Mining valid from 2019-01-06
Received: 19 July 2018
Accepted: 10 December 2018
First Online: 6 January 2019
Ethics approval and consent to participate
: All subjects gave written informed consent. The study was approved by the Regional Committee for Medical and Health Research Ethics (REC Central 2015/1758).
: Not applicable.
: The authors declare that they have no competing interests.
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